Sometimes, finding a good Firefox theme is hard to do. Thankfully though there are still themes out there like Qute that look great, are lightweight and don’t kick you in the face with a stylistic nightmare of clashing colors.
As one of the oldest themes for Firefox, that is still updated, you have to give credit where credit is due. The reason this theme has lasted since before Firefox 1.0 is clear. They keep the interface clear of clutter, the icons are polished, and it does not stray too far from the default Firefox style we are accustom to.
You can download the Qute theme for Firefox from the Firefox Add-ons web site. Go revisit one of the oldest, and maybe the best, alternative skins out there for Firefox.